Vitamin C and the Limeys

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Vitamin C and the Limeys : Sal and Dr. David Agus talk about the history of Scurvy and Vitamin C

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Sal: I am here with Dr. Agus who is a professor of Medicine and Engineering at the University of Southern California and what are we looking at right over here?
Dr Agus: You can see on the right top there is the Captain of the British Royal Navy named James Lind and he was a remarkable guy, actually he did one of the first clinical trials and I will tell you about him in a minute.
But in the Battle of Trafalgar between the British and the French he did something very clever, in that on his ships he had fresh fruit- he had limes, hence the term Lyme for the British soldiers.
What was amazing is that being out at sea for several weeks at a time, the soldiers would all start to
develop scurvy, which is a lack of vitamin C.
Sal: What happens to someone when they have scurvy?
Dr Agus: So the vitamin C is involved in collagen synthesis which is kind of the scaffolding of the body
and so your body starts to degrade, you start to get bleeding gums, your tissues start to fall apart.
And it ends up in death in most people if no vitamin C is given.
Sal: I see, all your connective tissue in your body starts to degrade
Dr Agus: Literally starts to degrade.
Sal: And it can't rebuild itself. Wow.
Dr. Agus: So in the late 90's I was working in a laboratory and I read his book, it's called "A Treatus Called Scurvy from 1746."
And in it, he said that, uh uh, talked all about doing autopsies on people with scurvy.
People my age, and I'm in my 40s have never seen scurvy, ever. So the first time I ever heard about scurvy and what it looked like was reading it.
And what he mentioned was that the brain was always intact in people with scurvy.
So when I looked to identify how vitamin C worked in the body, what the transporter was, the first place
I looked was the brain.
And science, it kind of overlooked looking there for this transporter because no one had read the book
in a long time. We cloned, which is identified the gene to allow vitamin C to go in and out of cells.
It's a pretty cool molecule because the Vitamin C that you eat is called ascorbic acid,
and in order to get it into cells, it has to be converted into another molecule called dehydroascorbic acid.
But what's amazing is, is that in the medical textbooks, as late as the 1920's
and 30's, they still called scurvy an infectious disease.
Because at the end of his book he put a paragraph where he said "I happen to sell the extract
of lime to prevent scurvy and it didn't work." And it didn't work because as soon as you squeeze
that lime at room temperature the vitamin C degrades.
And so, people tried to reproduce what he did and they couldn't.
And you know, he was an entrepreneur, he couldn't sell limes, cause everybody had limes,
so he tried to sell the extract of limes and it didn't work.
Sal: So even though he was able to, the clinical trial that he ran, was regarding limes
and scurvy.
Dr. Agus: Yes, he took these nuns and he gave them a diet that had
no fruits in it and then a diet with limes.
And he showed that the people who had the limes didn't develop scurvy
and others died.
Sal: So he just watched some nuns have, get scurvy and die.
Dr Agus: Not the most ethical experiment in the world.
Sal: No, no, yes. So he's not necessarily the most, the most...
Dr Agus: But, he did that in the 1740s and that was
Sal: ...ethical person in the world. But but, he he learned, that oh the limes will at least, it seemed, prevent scurvy.
Dr. Agus: Right. Remember, what a vitamin is, and this is key,
What a vitamin is is something the body can't synthesize enough of.
So for example, a mouse has an enzyme that allows it to synthesize vitamin C
So in a mouse, it wouldn't be called vitamin C, it would just be called ascorbic acid.
Cause it's not really a vitamin.
Sal: Interesting, interesting. So if we were mouse doctors,
we would just call it, we would just call it ascorbic acid.
Dr. Agus: Exactly. If we were mice, we'd call it ascorbic acid too!
Sal: Exactly!
Dr Agus: Um, or they probably have their own language.
Sal: Right, right.
Dr Agus: But, in all of us, we have certain things that we have to get from the outside from
food and those are called vitamins and minerals.
So a vitamin doesn't mean that more is better. Doesn't mean that it's good for you.
It just means that you require a small amount of it and your body can't synthesize it.
Sal: So this guy right here, he does a clinical trial with the nuns,
he figures out that lime, people who have fruit, who have lime are not getting
scurvy, and so he sends out a bunch of lime with the British, the Navy during the
Napoleonic wars, and that's why they're called Lymes.
And, I guess apparently, they won the war because of that.
Because once you're at war you're several weeks at sea,
the French navy is getting decimated with scurvy. Because they're not getting,
they're eating dry, they're eating beef jerky or whatever else they might be eating.
They're not getting fruit. So it's really, it's because of that of that
discovery, because of that discovery, the British won the battle of Trafalgar.
Dr Agus: Exactly. Two lessons from it.
One is, you know, you can't just say generically lime,
you matter how the fruit is, how it's cared for.
You know, once he juiced it and put it at room temperature, it was all gone.
Sal: Right, so besides the fact that this guy did a clinical trial that killed a bunch of nuns,
he also said 'Hey, this is a business opportunity"
Dr Agus: Right
Sal: I've just shown, maybe he felt that he didn't get compensated properly for saving the British
Fleet from Napoleon and says "I'm going to make a business out of this."
And so he decides to start taking lime juice extract and tries to sell it
as a cure for, what happened, why didn't he become rich?
Dr Agus: Because it didn't work.
Once you squeeze it out of the lime, it degrades the vitamin C.
Literally it's called 'oxidizes'. And it happens when it's
been exposed to light and oxygen in room temperature. Almost instantaneously!
Sal: I see. So what happened was, when the soldiers were eating the lime in the whole form,
sure you may chew on it a little bit, you might cut it a little bit, but there's
whole peices of lime that were not exposed, where the vitamin C wasn't exposed to the air
or whatever else, that actually got into someones system.
Dr Agus: Exactly. There's a reason Tropicana, when they sell you
orange juice, it's in a cardboard container that gets no light in and it's refrigerated.
Because that keeps the vitamin C intact.
Sal: Right. So because people didn't realize that, because they said, hey ok, for whatever reason
they didn't get scurvy during Traflagar
but, hey we have the lime extract and
that's not preventing scurvy, people kind of gave up on that whole hypothesis.
That it was about the vitamin C. And that's why you're saying, as
recent as the 1920's people
thought it was about, some type of infectious disease.
Dr. Agus: Exactly.
So, the key is when you start to look at data, you have to look at all aspects of it.
And somebody smart should have looked and said,
'Listen, how he did his first experiment was different than what he was selling and trying to validate"
Sal: That's interesting.
Dr Agus: If someone had looked at that for 200 years, we would have saved a lot of lives.
Because remember, it was from 1946 til the 1930's that we discovered what vitamin C
truly was.
And so a lot of lives were lost then because nobody paid attention
Sal: Fascinating. There's these other side affects of, one a vitamin doesn't necessarily mean a good thing.
That's something kind of programmed into us,
maybe by the nutracutical industry.
But, but, even if it is a good thing, it's not even necessarily a good thing to get it
in a processed form. And this isn't some type of, you know, some tree-hugging organic,
there's some science here that's like look, if something is an antioxidant
and it gets exposed to oxygen or some other oxydizing agent,
it's not going to be able to do any good any more.
Dr Agus: It's chemistry. Yeah.
Sal: So that's where the whole, the actual fruit is going to be more valued.
Dr. Agus: And remember, one orange has a couple of milligrams of vitamin C
One, two, three milligrams.
One pill has 500 milligrams.
Sal: Right.
Dr Agus: So whoever is making those pills kind of forgot what was going on in nature.
Sal: Right. Right, fascinating. This is very good.